1. Field of the Invention
The present invention generally relates to sound devices and more particularly to an improved microphone windscreen.
2. Prior Art
A wide variety of applications in science, industry and entertainment require high quality reproduction of sound using available sound recording techniques and equipment. High-quality, low-noise sound reproductions, for example, are of critical importance in the television and movie industry. There, crisp, clean voice and dialogue reproduction must be achieved despite ambient and background noise levels of moderate to high amplitude.
One frequently encountered source of undesirable background noise is caused by air moving relative to the sound transducing device, which is most typically an omnidirectional or unidirectional microphone. As a result, a "whooshing" or rushing sound is imposed on the desired audio, thus resulting in deteriorated sound quality.
This type of noise may occur due to environmental or operational requirements and conditions. For example, wind noise often occurs when a microphone is panned during an indoor shoot, whether on a boom or simply held in hand with an extension. Likewise, such noise may be caused by forced air movement such as by fans or dynamic special effects equipment.
In certain applications, such as speeches or movie productions, unidirectional microphones are used which can reject most rear and lateral wind noise. However, this reduction is only effective at very low relative velocities, and will not reduce head-on wind noise. Further, unidirectional microphones are not suitable for all applications.
There are several prior art schemes that have been employed in an attempt to eliminate or reduce microphone wind noises. One is the use of a foam "sock" which is pulled over the microphone head. However, foam socks tend to physically deteriorate over time. As a result, foam particulates often fall into the microphone head, causing damage and reduced performance. Also, foam socks suffer the drawback of only being effective to reduce wind noise due to very slight breezes, up to approximately three miles per hour. This is a severe limitation in a broad spectrum of standard outdoor and indoor operating environments essential to the film and television industry. To overcome this limitation, electronic filtering techniques have been used to filter out wind noise resulting from velocities exceeding three miles per hour. Unfortunately, electronic filtering also attenuates desired audio frequencies, thereby substantially degrading sound quality.
An improved form of microphone windscreen is disclosed in U.S. Pat. No. 4,600,077. That device is slidably receivable for resiliently retaining the wind shroud in place. The mounting means incorporates a combination closed-cell and open-cell foam suspension support sections.
The wind shroud of the patent is a narrow cylindrical body which aligns with the shape of the microphone and can therefore fit between the narrow spaces provided between the microphone mount and the camera in modern video camera equipment. A grid-like structure covered with a multilayer laminate material provides for attenuation of undesired wind noise of speeds of up to 25 miles per hour while allowing desired audio frequencies, such as speech and music to pass freely to the transducer element of the microphone. A microphone wind shroud thus is provided that can easily and inexpensively manufactured while providing superior attenuation over prior art attenuation methods. Moreover, it is compact enough to be used with modern day microphones mounted to mini-camera equipment.
Unfortunately the wind shroud (windscreen) is fabricated of three separate pieces joined together in a manner which makes them subject to breakage if and when the wind shroud is bumped, dropped or otherwise distorted. In this regard, the tubular main body of the device has at one end thereof an end cap abutting it and held in place thereagainst by a raised plastic ring. At the opposite end of the main body a raised plastic cup or fitting (mount) is glued to the main body. The resulting uneven outer surface of the device has higher than optimal wind resistance. Thus, it causes wind to deflect therefrom and results in some undesired wind noise, including a sibilance and/or rumble.
Accordingly, there remains a need for an improved microphone windscreen which is strong, resilient, resistant to crushing and other breakage and has improved low wind resistance and improved acoustical properties. The wind screen should be inexpensive, durable and efficient.